1. Field of the Invention
The present invention generally relates to optical information recording apparatuses, information processing apparatuses, optical information recording media, optical information recording methods and computer-readable storage media, and more particularly to an optical information recording apparatus and an optical information recording method for recording information on an optical information recording medium having a multi-layer structured recording layer made up of a plurality of recording layers each capable of recording information, an optical information recording medium having a recording layer with a multi-layer structured recording layer made up of a plurality of recording layers each capable of recording information, an information processing apparatus having such an optical information recording apparatus for recording information on such an optical information recording medium, and a computer-readable storage medium which stores a program for causing a computer to record or to control an optical information recording apparatus to record information on such an optical information recording medium having the multi-layer structured recording layer.
2. Description of the Related Art
For example, a Japanese Laid-Open Patent Application No. 11-195243 proposes a recording medium having a multi-layer structured recording layer, and recording and reproducing methods for such a recording medium.
In addition, a Japanese Laid-Open Patent Application No. 2002-50053 proposes a technique for recording information that is unique to a data layer in each of the data layers forming a multi-layer structured recording layer of an optical medium.
Furthermore, a Japanese Laid-Open Patent Application No. 2000-311346 proposes an Optimum Power Control (OPC) with respect to an optical disk having a multi-layer structured recording layer.
Due to the popular use of multi-media, music CDs, CD-ROMs, read-only media (recording media) such as DVD-ROMs, and information reproducing apparatuses therefor have been reduced to practice. Recently, much attention is drawn to write-once optical disks using dye media, rewritable Magneto-Optic (MO) disks using MO media, and phase change type media, and information recording and reproducing apparatus which use such recording media have also been reduced to practice. Rewritable DVD media are expected to become the next-generation multi-media recording media and large-capacity storage media.
The phase change type media record the information by making a reversible phase change of a recording material between a crystal phase and an amorphous phase. Unlike the MO media and the like, the phase change type media do not require an external magnetic field, and information can be recorded on and reproduced from the phase change type media by simply irradiating a laser beam from a light source such as a semiconductor laser onto the phase change type media. Furthermore, an overwrite recording can be made with respect to the phase change type media by the laser beam which simultaneously carries out the erasure and recording of the information.
For example, as a general recording waveform for use in making a recording on the dye media, there is a single-pulse semiconductor laser emission waveform that is generated based on an 8–16 modulation code or the like. When using the single-pulse recording waveform for the recording, a recording mark may become distorted to a tear-drop shape due to accumulated heat. For this reason, as a Laser Diode (LD) light emission waveform strategy for recording information on the dye media, a system has been proposed to form marks on the dye media by use of a laser beam having a multi-pulse waveform based on recorded data such as an EFM modulation code, as shown in FIG. 1(c). FIG. 1 is a timing charge showing a channel clock, an 8–16 modulated signal and an optical waveform in the optical information recording and reproducing apparatus. FIG. 1(a) shows the channel clock, and FIG. 1(b) shows the 8–16 modulated signal. A system has been proposed to form a mark portion of the multi-pulse waveform shown in FIG. 1(c) by a leading heating pulse and a plurality of consecutive heating pulses which follow the leading heating pulse. In FIG. 1(c), Pw denotes a write power (power when the heating pulse is ON), Pb denotes a bias power (power when the heating pulse is OFF), Pr denotes a read power, A denotes the leading heating pulse, B denotes the plurality of consecutive heating pulses, C denotes consecutive cooling pulses between the consecutive heating pulses, an D denotes an erase pulse. Normally, the power is not turned OFF completely when the heating pulse is OFF, and the bias power Pb which is approximately the same as the read power Pr is applied.
Generally, an optimum value of the recording power when making the recording with respect to the optical recording medium changes depending on an ambient temperature, the kind of recording medium, a linear velocity and the like. Hence, when making the recording with respect to the dye medium or the phase change type medium, the optical information recording apparatus optimizes the recording power prior to recording the information by carrying out the Optimum Power Control (OPC) which performs a test write. The OPC is carried out by recording predetermined information in a predetermined area of the recording medium called a Power Calibration Area (PCA), and reproducing the predetermined information.
More particularly, test data having a predetermined pattern made up of marks and spaces amounting to 3 times (3T) to 14 times (14T) of a period T of the channel clock, are recorded on the optical recording medium by varying the light emission power in several levels. The recorded test data are reproduced, and a DC modulation of an RF signal, an asymmetry of the RF signal after AC coupling, and the like at each power level are calculated as evaluation references. A modulation M may be calculated as follows, where Ip−p denotes a maximum amplitude of the RF signal and Imax denotes a maximum value of the RF signal.M=Ip−p/Imax  (1)
In addition, an asymmetry β after the AC coupling may be described by the following, where X1 denotes a positive peak level of the RF signal after the AC coupling, X2 denotes a negative peak level of the RF signal after the AC coupling.β=(X1+X2)/(X1−X2)  (2)In the above, “X1+X2” indicates a difference between the positive and negative peak levels of the RF signal after the AC coupling, and “X1−X2” indicates a peak-to-peak value of the RF signal after the AC coupling.
The optimum recording power is obtained based on the modulation M and the asymmetry β after the AC coupling described above.
When recording information on the write-once or rewritable medium, it is necessary to set the recording conditions depending on the type of the medium. Generally, the recording conditions include the setting of the recording power and the setting of the recording pulse shape that are used when carrying out the OPC. In a case where the optical information recording apparatus is capable of specifying the type (manufacturer's name, type identification information, etc.) of the medium to which the recording is to be made, the recording conditions for the medium may be prestored in a memory within the optical information recording medium. In the case of the DVD+R and DVD+RW media, the manufacturer and type of the medium are prerecorded in a wobble signal recorded in a pre-groove that is formed on a recording track, called an Address In Groove (ADIP), in a predetermined region of the medium.
In a case where the optical recording apparatus is not capable of specifying the type of the medium (unknown medium), the recording conditions that are specified by the manufacturer of the medium are recorded in the ADIP information in the predetermined region, and thus, the recording power setting and the recording pulse shape can be determined based on the recording conditions when carrying out the OPC.
As one approach to increase the amount of information recorded on the optical recording medium as compared to the conventional case, there is a known technique that forms the recording surface by multiple layers. In the DVD-ROM media, this technique is already reduced to practice for media having the recording surface with a 2-layer structure. As described above, the structure and the recording method for the recordable medium having the multi-layer structured recording layer are proposed in the Japanese Laid-Open Patent Application No. 11-195243, for example.
In a case where the multi-layer structured recording layer is employed in the write-once or rewritable media, the recording conditions must be set for each layer forming the multi-layer structured recording layer since the recording characteristics differs for each layer forming the multi-layer structured recording layer.
If the optical information recording apparatus is capable of specifying the type of the medium, the recording conditions for each layer forming the multi-layer structured recording layer may be prestored in the memory within the optical information recording apparatus. But if the optical information recording apparatus is not capable of specifying the type of the medium, such as the case where the type of the medium is unknown, optimum recording conditions cannot be set for each layer forming the multi-layer structured recording layer, to thereby deteriorate the recording quality.
In the case of the medium recorded with the recording conditions of each layer forming the multi-layer structured recording layer in each layer as proposed in the Japanese Laid-Open Patent Application No. 2002-50053, the recording conditions can be read from each layer forming the multi-layer structured recording layer even if the medium is unknown to the optical information recording apparatus.
But conventionally, there is no known optical information recording apparatus which carries out the OPC, with respect to the medium recorded with the recording conditions of each layer forming the multi-layer structured recording layer in each layer of the multi-layer structured recording layer, using the recording conditions of each layer reproduced from the medium.